Arterial Stiffness in Renal Transplant Recipients: 5-Year Follow-up

Background. Chronic kidney disease is a risk factor for cardiovascular diseases. After renal transplant, some traditional and chronic kidney disease-specific risk factors vanish, but new risk factors emerge. This retrospective study aimed to define the long-term impact of renal transplant and diabetes mellitus on arterial stiffness, evaluated by measuring pulse wave velocity (PWV) and augmentation index (AI) and on myocardial perfusion, evaluated by subendocardial viability ratio (SEVR). Methods. PWV, AI, and SEVR were evaluated noninvasively by applanation tonometry using SphygmoCor in the first 4 weeks after kidney transplant and 4 to 5 years thereafter. Results. A total of 48 graft recipients (18 women, 30 men; mean +/- standard deviation age, 47.9 +/- 11.8 years) were included. The follow-up period was 57.4 +/- 8.0 months. PWV did not change significantly during the follow-up period (9.1 +/- 1.8m/s and 8.7 +/- 1.8m/s, respectively; P = .137). In the subgroup of patients without diabetes mellitus, we observed a trend of PWV reduction, whereas in the subgroup of patients with diabetes we observed the trend of PWV increase. The duration of smoking before transplant correlated significantly with PWV (P = .012). AI in the whole group increased significantly during the study period (from 18.3% +/- 10.3% to 25.9% +/- 9.4%; P < .01) as well as SEVR (from 134.9 +/- 23.1 to 155.4 +/- 28.6; P = .001). Conclusions. PWV, reflecting the central vessel stiffness, did not change significantly in the whole group during the follow-up period. The AI, which indicates systemic stiffness, increased significantly within 5 years after transplant, indicating the progression of vascular processes of elastic and muscular arteries. Significant increases in the SEVR values in both diabetics and non-diabetics indicate the long-term favorable effect of kidney transplant on myocardial perfusion.